1. Field of the Invention
The present invention relates generally to building structures, and in particular to a structural insulated panel system therefor.
2. Description of the Prior Art
In the construction of various types of buildings, the walls, roofs, ceilings and floors thereof typically support both live (occupant) and dead (structure) loads in a structural capacity and also thermally insulate the space enclosed thereby. Heretofore, a variety of different construction techniques have been devised for combining these functions.
For example, conventional frame construction is widely employed in residential and other types of construction. Typically, a wood frame for the structure is constructed with load-bearing walls comprising studs, top and bottom plates and headers over the openings. Floor and ceiling joists span between the walls. During or after the framing stage, sheathing and/or siding is typically applied to the exteriors of the walls. The walls are then insulated with, for example, fiberglass insulation for controlling thermal conduction therethrough. Insulation is also typically placed between the ceiling joists or roof rafters and between the floor joists over unheated areas. The wall interiors generally comprise a layer of gypsum board, paneling or the like.
Although widely used, the aforementioned frame construction techniques have several drawbacks. For example, they tend to be relatively labor-intensive with most of the assembly taking place on the job site. Weather conditions often delay and hamper such projects and can damage the construction materials before the structure can be enclosed and made weathertight. Furthermore, difficulties can be encountered in controlling quality on the job site, particularly under adverse weather conditions. Yet another disadvantage is that conventional wood frame construction often produces structures which are relatively inefficient to heat and cool. One source of heat loss is the structural studs themselves, which provide thermal bridges for conducting heat between the exterior ambient atmosphere and the enclosed space.
In order to overcome some of the aforementioned disadvantages with site-built frame construction, wall panel systems have heretofore been devised which provide wall panels which are both structural and thermally insulated. For example, the Douglas U.S. Pat. No. 3,133,322 and the Smith U.S. Pat. No. 4,163,349 disclose prefabricated, insulated building panels. However, the panels disclosed in these patents include areas with materials which are not particularly effective as thermal insulation and which thus permit undesired heat gain and loss.
Heretofore, there has not been available a structural insulated panel system with the advantages and features of the present invention.